Aircraft Scatter - Lentokoneheijastus ja sen doppleri.

Keskustelua antenneista, radioista, yms. radioamatööritekniikasta

Strong 6m TV High Sky Scatter - Part 2

ViestiKirjoittaja OH7HJ » 11.12.2017 14:42

Soon after I had reported about the wide strong natural scatter there appeared an aurora scatter. The aurora was a short burst lasting for a couple hours only. After aurora had stepwise faded out, there appeared one more wide natural burst following it. After this there were no similar strong natural wide bursts for hours.

It might be possible that these wide strong scatters were once again related to high sky electrostatic discharge activity, like accumulating high voltage ionospheric charges that seem to be related to birth of aurora borealis (Northern lights), too?

Solar wind is known to constantly bring positive static high voltage charges to the upper ionosphere. Electrostatic explanation of Northern lights discharge suggests that aurora borealis is a high voltage discharge between polar rims of ionosphere opening (aurora belt) and charged solar wind environment. This model explains easily the curtain shapes of visible aurora discharges in the sky, as well as aurora discharge movements along with night time movement of polar opening of ionospheric layers.

Strong 6m TV High Sky Scatter - Part 1: viewtopic.php?f=21&t=295&p=2420#p2420


- Juha -
Liitteet
2017-12-10-1842 Pielinen HDSDR OIRT1 Y6E 030 - After wide strong EDS flare aurora scatter igniting (c) OH7HJ.JPG
2017-12-10-1842 Pielinen HDSDR OIRT1 Y6E 030 - After wide strong EDS flare aurora scatter igniting (c) OH7HJ.JPG (156.19 KiB) Katsottu 1479 kertaa
2017-12-10-2020 Pielinen HDSDR OIRT1 Y6E 030 - Strong wide EDS flares before and after short aurora burst (c) OH7HJ.jpg
2017-12-10-2020 Pielinen HDSDR OIRT1 Y6E 030 - Strong wide EDS flares before and after short aurora burst (c) OH7HJ.jpg (123.47 KiB) Katsottu 1479 kertaa
2017-12-10-2137 Pielinen HDSDR OIRT1 Y6E 030 - Strong wide EDS flares before and after short aurora burst (c) OH7HJ.jpg
2017-12-10-2137 Pielinen HDSDR OIRT1 Y6E 030 - Strong wide EDS flares before and after short aurora burst (c) OH7HJ.jpg (191.89 KiB) Katsottu 1479 kertaa
OH7HJ
 
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Strong 6m TV High Sky Scatter - Part 3

ViestiKirjoittaja OH7HJ » 18.12.2017 00:41

Oheiskuvana on leveä tutkanauha aurorapurkauksesta, sekä sitä ennen ja sen jälkeen esiintyneistä leveistä ja voimakkaista korkean taivaan luonnollisista sähkönpurkausheijastuksista (EDS). Nauhan alalaidassa näkyvät edellisen aamuyön aurorapurkausheijastusten pätkät.

Näiden vahvojen sähkönpurkausten luonnetta ei vielä tunneta. Niillä on kuitenkin luonnollisten korkean taivaan sähkönpurkausten moduloimille radioheijastuksille luonteenomainen hajaspektri. Arvauksen mukaan ne saattavat liittyä ylempiin ionosfäärisalamiin.

Revontulipurkausten radioheijastukset (Aurora Scatter) sekä voimakkaat leveät sähkönpurkausheijastukset (Wide EDS) on ympyröity spektrinauhalle. Aikaisempia havaintoraportteja samankaltaisista voimakkaista sähkönpurkausheijastuksista ennen ja jälkeen revontulipurkausten:

Strong 6m TV High Sky Scatter - Part 1 - viewtopic.php?f=21&t=295&start=160#p2420
Strong 6m TV High Sky Scatter - Part 2 - viewtopic.php?f=21&t=295&p=2421#p2421

Vastaanottimena havainnossa on RTL-SDR, softana HDSDR, ja antennina 6-el 50 MHz jagi suunnattuna pohjoiseen.


T: - Juha
Liitteet
2017-12-17-2303 FT - OIRT1 HDSDR Y6H 360 - Aurora discharge scatters with wide EDS bursts between and after (c) OH7HJ.JPG
2017-12-17-2303 FT - OIRT1 HDSDR Y6H 360 - Aurora discharge scatters with wide EDS bursts between and after (c) OH7HJ.JPG (283.16 KiB) Katsottu 1454 kertaa
OH7HJ
 
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Strong 6m TV High Sky Scatter - Part 4

ViestiKirjoittaja OH7HJ » 20.12.2017 13:08

Lisää arvoituksellisia leveitä ja voimakkaita korkean taivaan sähkönpurkausheijastuksia tutkanauhoilla.

Näköhavaintoja kaivattaisiin ilmiöiden tunnistamiseksi, mutta niitä on tunnetusti vaikeaa saada täältä pilvien alta...

Nämä näkyivät eilen pohjoisen suuntaa havainnoivalla antennilla. Samankaltaisia näkyy satunnaisesti myös idän suunnalla. Aikaleimat ovat Suomen aikaa.


Strong 6m TV High Sky Scatters:

Part 1 - viewtopic.php?f=21&t=295&start=160#p2420
Part 2 - viewtopic.php?f=21&t=295&p=2421#p2421
Part 3 - viewtopic.php?f=21&t=295&start=170#p2426
Part 4 - viewtopic.php?f=21&t=295&start=170#p2427

Kuva: 2017-12-19-2034 FT - OIRT1 HDSDR SL Y6E 360 Segezha - Three wide EDS bursts (c) OH7HJ.JPG


T: - Juha
Liitteet
2017-12-19-2034 FT - OIRT1 HDSDR SL Y6E 360 Segezha - Three wide EDS bursts (c) OH7HJ.JPG
2017-12-19-2034 FT - OIRT1 HDSDR SL Y6E 360 Segezha - Three wide EDS bursts (c) OH7HJ.JPG (162.81 KiB) Katsottu 1448 kertaa
Viimeksi muokannut OH7HJ päivämäärä 20.12.2017 13:27, muokattu yhteensä 1 kerran
OH7HJ
 
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Supersähkönpurkaus vie voimaa revontulilta?

ViestiKirjoittaja OH7HJ » 30.12.2017 21:49

Leveänä nauhana tutkakuvassa näkyvä voimakas sähkönpurkausheijastus osui yksiin tutkassa pystysuuntaisina 'lieskoina' näkyvän alkavan revontulipurkauksen tilapäisen taukoamisen kanssa.

Leveän tutkanauhan kuvaa: 2017-12-30-2025 FT - OIRT1 HDSDR Y6H 360 Segezha TV - Wide EDS during pause of aurora discharge (c) OH7HJ


T: - Juha
Liitteet
2017-12-30-2025 FT - OIRT1 HDSDR SL Y6H 360 Segezha TV - Wide EDS during pause of aurora discharge (c) OH7HJ.jpg
2017-12-30-2025 FT - OIRT1 HDSDR SL Y6H 360 Segezha TV - Wide EDS during pause of aurora discharge (c) OH7HJ.jpg (107.83 KiB) Katsottu 1421 kertaa
OH7HJ
 
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Strong 6m TV High Sky Scatter - Part 6

ViestiKirjoittaja OH7HJ » 01.01.2018 18:55

Uudenvuodenpäivän iltapäiväinen revontulipurkaus oli varsin voimakas, ja sekaan leimahteli leveitä voimakkaita yläsalamapurkausten radiokaikuja. Tavallisesti aurorapurkausta ja tällaisia voimakkaista leveitä yläsalamaheijastuksia ei näy yhtaikaa, vaan leveät sähkönpurkausheijastukset esiintyvät ennen revontulipurkausta, tai sen jälkeen.

Arvaan purkausten yhtaikaisuuden ja voimakkuuden saattavan merkitä, että aurinkotuulen puhuri on tuonut aimo annoksen taivassähköä. Nyt aurinkotuulen tuomaa sähkövarausta lienee tullut riittävästi purkautumaan samanaikaisesti sekä revontulina, että yläsalamoina..?

Leveät korkean taivaan sähkönpurkausheijastukset näyttävät liittyvän joskus revontulten alkamiseen tai päättymiseen. Niin kävi nytkin. Aurorapurkaus taukosi klo 16.45, minkä jälkeen leimahti revontulitutkan nauhalle yksi voimakas leveä sähkönpurkauskaiku lisää. Revontulikaiut näkyvät tällä leveällä nauhalla pystysuuntaisina 'lieskoina'. Leveät sähkönpurkausheijastukset puolestaan näkyvät vaakasuuntaisina, yläreunaltaan sahalaitaisina juovina.

Tutkanauhan alemman ikkunan radiospektrinauhan liikesuunta on ylhäältä alaspäin. Aikaleimat nauhan vasemmassa reunassa ovat Suomen aikaa. Päiväys on kuvien tiedostonimessä. Taajuudet näkyvät kilohertseinä taajuusasteikolla spektri-ikkunoiden välissä.


T: - Juha
Liitteet
2018-01-01-1646 FT - OIRT1 HDSDR Y6H 360 Segezha TV - Aurora and three wide strong EDS discharges (c) OH7HJ.jpg
2018-01-01-1646 FT - OIRT1 HDSDR Y6H 360 Segezha TV - Aurora and three wide strong EDS discharges (c) OH7HJ.jpg (114.68 KiB) Katsottu 1405 kertaa
2018-01-01-1717 FT - OIRT1 HDSDR SL Y6E 360 Segezha TV - Three wide EDS bursts and one more occurring (c) OH7HJ.JPG
Leveät korkean taivaan sähkönpurkausheijastukset näyttävät liittyvän joskus revontulten alkamiseen tai päättymiseen. Niin kävi nytkin. Aurorapurkaus taukosi klo 16.45, minkä jälkeen leimahti revontulitutkan nauhalle yksi voimakas leveä sähkönpurkauskaiku lisää.

Revontulikaiut näkyvät tällä leveällä nauhalla pystysuuntaisina 'lieskoina'. Leveät sähkönpurkausheijastukset puolestaan näkyvät vaakasuuntaisina, yläreunaltaan sahalaitaisina juovina.

Tutkan ylemmässä spektri-ikkunassa näkyy parhaillaan tapahtuvamassa olevan leveän EDS-yläsalamapurkauksen (Electric Discharge Scatter) hetkellinen spektri, jonka muoto kertoo sen olevan ilmeinen TV-kuvalähetteen heijastus toistaiseksi tunnistamattomalta R1-kanavan TV-lähettimeltä.

Havaintoantennina on pohjoiseen suunnattu 6-el 50 MHz vaakajagi, ja vastaanottimena RTL-SDR.
2018-01-01-1717 FT - OIRT1 HDSDR SL Y6E 360 Segezha TV - Three wide EDS bursts and one more occurring (c) OH7HJ.JPG (84.16 KiB) Katsottu 1405 kertaa
OH7HJ
 
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Multi Freq Monitoring with Single Rx and Aerial - 1.

ViestiKirjoittaja OH7HJ » 02.02.2018 11:36

A simple multi-frequency reception experiment on part of 49750 kHz OIRT1 TV channel spectrum with traditional analog HF communications receiver Plessey PR155 which has filter for 6 kHz wide USB. This is a moderate increase of rx bandwidth which allows receiving two instead of previous one TV tx carrier frequencies at the same time with single aerial and receiver. Here the two freqs are Moscow TV and St Petersburg TV carriers about 3 kHz apart from each other.

First screenshot shows an aurora discharge burst at left on 5.5 kHz wide bandwidth Spectrum Lab display from part of the R1 TV channel spectrum. Moscow TV and St Petersburg at wide spectrum strip left and St Petersburg zoomed as detail at right SL strip. Both were received simultaneously with same receiver and aerial. Scale at top of each strip shows frequency as Hz.

SL2 Y6U PR155 OIRT1 5.5 kHz wide spectrum - Moscow - St Petersburg (c) OH7HJ - 2018-02-01-0100 - Aurora burst.jpg


Second screenshots shows at left strip Moscow TV and at right strip St Petersburg TV carrier aurora bursts zoomed still wider with simultaneously plotting another example of Spectrum Lab reading the same PR155 receiver through tiny USB audio stick. Sorry for heavy freq drift of the veteran rx and its converter. Neither are near modern stability standards.

The two Spectrum Labs reading receiver sound through an USB audio dongle consume minimal amount of computer power. The same computer reads and plots at the same time sound inputs from two more 50 MHz ham receivers with still one SL example, plus listens to aircraft ADS-B signals with a RTL1090 SDR to plot them on Planeplotter map: https://maanpuolustus.net/pages/tutka/

This makes a single computer monitor, analyze and save simultaneously 6 spectrum strips and 5 frequencies. Processing power of this pre-Millennium era Fujitsu Scenic desktop running multi analog rx's and SL windows is about similar to modern Raspberry Pi. Multi frequency and multi spectrum analysis from wide band audio sound feed from single receiver and aerial appears feasible.

SL3 Y6U PR155 OIRT1 - Zoomed from 5.5 kHz wide spectrum - Moscow and St Petersburg (c) OH7HJ - 2018-02-01-0100 - Aurora burst.jpg


On third screenshot an example of how switching Plessey receiver filters affect monitored bandwidth visible on Spectrum Lab strips.

Filter responses are rather bumpy which is normal for analog receivers like PR155. Modern SDR's produce nice flat and straight frequency spectrums from their digital filters. I hope that I can get some of the new wide audio SDR's work in my computers to continue multi frequency experiments with.

2018-02-01-1223 SL3 Y6U PR155 OIRT1 - 5.5 kHz wide USB spectrum - Comparing bandwidths of 0.3 and 3 and 6 kHz rx USB filters (c) OH7HJ.jpg


Regards,

- Juha -
Liitteet
SL2 Y6U PR155 OIRT1 5.5 kHz wide spectrum - Moscow - St Petersburg (c) OH7HJ - 2018-02-01-0100 - Aurora burst.jpg
Aurora scatter burst at left on 5.5 kHz wide bandwidth Spectrum Lab display from part of the R1 TV channel spectrum. Moscow TV and St Petersburg at wide spectrum strip left and St Petersburg zoomed as detail at right SL strip. Both were received simultaneously with same receiver and aerial. Scale at top of each strip shows frequency as Hz.
SL2 Y6U PR155 OIRT1 5.5 kHz wide spectrum - Moscow - St Petersburg (c) OH7HJ - 2018-02-01-0100 - Aurora burst.jpg (374.41 KiB) Katsottu 1304 kertaa
SL3 Y6U PR155 OIRT1 - Zoomed from 5.5 kHz wide spectrum - Moscow and St Petersburg (c) OH7HJ - 2018-02-01-0100 - Aurora burst.jpg
Second screenshots shows at left strip Moscow TV and at right strip St Petersburg TV carrier aurora bursts zoomed still wider with simultaneously plotting another example of Spectrum Lab reading the same PR155 receiver through tiny USB audio stick. Sorry for heavy freq drift of the veteran rx and its converter. Neither are near modern stability standards.
SL3 Y6U PR155 OIRT1 - Zoomed from 5.5 kHz wide spectrum - Moscow and St Petersburg (c) OH7HJ - 2018-02-01-0100 - Aurora burst.jpg (371.27 KiB) Katsottu 1304 kertaa
2018-02-01-1223 SL3 Y6U PR155 OIRT1 - 5.5 kHz wide USB spectrum - Comparing bandwidths of 0.3 and 3 and 6 kHz rx USB filters (c) OH7HJ.jpg
An example of how switching Plessey receiver filters affect monitored bandwidth visible on Spectrum Lab strips.

Filter responses are rather bumpy which is normal for analog receivers like PR155. Modern SDR's produce nice flat and straight frequency spectrums from their digital filters. I hope that I can get some of the new wide audio SDR's work in my computers to continue multi frequency experiments with.
2018-02-01-1223 SL3 Y6U PR155 OIRT1 - 5.5 kHz wide USB spectrum - Comparing bandwidths of 0.3 and 3 and 6 kHz rx USB filters (c) OH7HJ.jpg (152.15 KiB) Katsottu 1304 kertaa
OH7HJ
 
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Multi Freq Monitoring with Single Rx and Aerial - 2.

ViestiKirjoittaja OH7HJ » 03.02.2018 11:55

Continued from previous message.

Equipment pics: A 50 MHz converter equipped Plessey PR155 HF receiver dating from early 1970's was used with this experiment because it was my only rx that could listen to rather wide audio USB with its AM filter of about 6 kHz bandwidth and adjustable beat.

Only digitizing device between the PR155 receiver and computer was an inexpensive USB sound stick.


Regards,

- Juha -
Liitteet
IMG_7717 Plessey PR155 HF comms receiver (c) OH7HJ.JPG
Plessey PR155 HF receiver dating from early 1970's was used with this experiment because it was my only rx that could listen to rather wide audio USB with its AM filter of about 6 kHz bandwidth and adjustable beat.
IMG_7717 Plessey PR155 HF comms receiver (c) OH7HJ.JPG (62.06 KiB) Katsottu 1299 kertaa
IMG_7722 USB sound stick.JPG
Only digitizing device between the PR155 receiver and computer was this sound stick.
IMG_7722 USB sound stick.JPG (23.79 KiB) Katsottu 1299 kertaa
OH7HJ
 
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Curious circling flight track doppler

ViestiKirjoittaja OH7HJ » 12.02.2018 11:33

A regular repeating flight pattern doppler appeared on St Petersburg TV and Segezha Nadvoitsy TV strips. It appeared to belong to an ATR plane of flight FIN51G circling around. Doppler vanished as the plane apparently descended below Tx radar horizon for landing to EFJO.

FR24 map view plotted some irregularities to its track. Reason is that this ATR carries only the 'old style' mode A/C transponder which does not transmit GPS location of the aircraft.

The FR24 receiver network uses for non-ADS-B mode-S transponder flights MLAT means of locating by its signal time difference of arrival (TDOA). MLAT is less accurate than ADS-B and causes deviations of plane location here visible as aircraft fake sudden jumps southeast on the FR24 playback map. Dopplers tell its real movements.

Online archive spectrum strips of the circling flight doppler:

https://maanpuolustus.net/muut/tutka/ku ... /11_30.jpg
https://maanpuolustus.net/muut/tutka/ku ... /12_00.jpg


- Juha
Liitteet
2018-02-10-1108-2 FR24 pb - D4H St Petersburg - Y12H 100 Segezha TV - Curious flight pattern doppler of ATR FIN51G - (c) OH7HJ.JPG
2018-02-10-1108-2 FR24 pb - D4H St Petersburg - Y12H 100 Segezha TV - Curious flight pattern doppler of ATR FIN51G - (c) OH7HJ.JPG (263.53 KiB) Katsottu 1219 kertaa
OH7HJ
 
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Mobile Multi Frequency Doppler Reception - 1.

ViestiKirjoittaja OH7HJ » 25.02.2018 11:55

An experiment with a multi frequency receiving configuration aboard a car to see what kind dopplers one gets while moving on road. Receiver was a common RTL-SDR with newest version of software SDR Console V3 which Jesse OH2BIX kindly instructed me how to configure to provide R1 TV wide band voice containing all TV transmitter carriers of doppler interest, thank you!

The wide band 'radar sound' from SDR-V3 was further streamed through VB-Cable mixer software to 10 separately configured Spectrum Lab windows. From this 'doppler radar voice' were separated and plotted narrow band detail strips of eight R1 TV channel transmitters plus a wide band spectrum of entire 22 kHz wide central R1 TV spectrum. This configuration allows monitoring, measuring and saving simultaneously all carriers of the OIRT1 band with a single receiver and single aerial using easily available free software.

Receiving aerial was a horizontal omnidirectional V-dipole built of carbon fiber rods and of glass fiber broom shaft attached to wooden mounting piece held on car roof by magnets. A Thinkpad T61 laptop was running the receiving software with RTL receiver attached to its USB port.


Links:

R1 TV channel wide band 'doppler radar voice' online demo: https://maanpuolustus.net/pages/tutka/

SDR Console V3 receiving software: http://www.sdr-radio.com/Software/Downloads

VB-CABLE Virtual Audio Device: https://www.vb-audio.com/Cable/

Broadband twin lead match for a 6m band dipole: viewtopic.php?f=21&t=228#p1104


- Juha
Liitteet
SL6 RTL SDRV3 St. Petersburg TV (c) OH7HJ - 2018-02-23-0900 - Detail of on road mobile receiving experiment spectrum strip with aircraft doppler.jpg
An example of one of TV Tx carrier detail strips automatically saved by Spectrum Lab. On road movement of the car caused doppler shifts to the TV carrier making it twisty. :)
SL6 RTL SDRV3 St. Petersburg TV (c) OH7HJ - 2018-02-23-0900 - Detail of on road mobile receiving experiment spectrum strip with aircraft doppler.jpg (59.42 KiB) Katsottu 1141 kertaa
2018-02-22 R1 TV aircraft scatter multi frequency measuring receiver setup in car (c) OH7HJ.JPG
Measurin laptop running software. For charging on the run its power lead was attached to car 12 V system. When car motor is running its battery charging voltage rises up to almost 15 volts which is enough for powering up the laptop without need of separate voltage step-up adapters which tend to cause unwanted RF interference.
2018-02-22 R1 TV aircraft scatter multi frequency measuring receiver setup in car (c) OH7HJ.JPG (151.49 KiB) Katsottu 1141 kertaa
2018-02-23-Car - R1 TV receiving dipole mounted to car roof for mobile doppler experiment (c) OH7HJ.JPG
Mobile doppler receiving aerial was a horizontal omnidirectional V-dipole built of carbon fiber rods and of glass fiber broom shaft attached to wooden mounting piece held on car roof by magnets. Thin whip aerial at left is for ham 144 MHz APRS.
2018-02-23-Car - R1 TV receiving dipole mounted to car roof for mobile doppler experiment (c) OH7HJ.JPG (67.26 KiB) Katsottu 1141 kertaa
OH7HJ
 
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Mobile Multi Frequency Doppler Reception - 2.

ViestiKirjoittaja OH7HJ » 25.02.2018 12:43

A combined Spectrum Lab display of multi freq receiving experiment detail strips of TV carriers from receiver in a moving car. Some of the carrier freq drift visible on St Petersburg and Segezha TV strips is from RTL receiver drift but much of it is caused by moving car velocity doppler shift. Joutseno TV and FM broadcast mast strong RF field appeared to deafen the RTL receiver stick at around 11.20 to 11.30 oc on this six TV frequencies set of spectrum detail strips causing black sections on them.

The first part of mobile measuring drive was to general direction of south and southwest. As the mobile receiver was driving farther away from Segezha Nadvoitsy TV Tx its signal faded and tended to shift a little down by doppler effect of car velocity. At the same time the mobile Rx was approaching nearer St. Petersburg TV Tx in south which caused its signal level to increase and shift a little upwards by doppler effect. However, when the 'twists' of both carriers are to the same direction it is probably caused by RTL Rx freq drift. Those twists that are to opposite directions between the two TV carriers are caused by car velocity doppler shift of reception.

The SDR V3 receiving software was set to stream a 22 kHz wide voice of two wide filter USB VFO's divided to both stereo channels of a single audio stream channel. This stereo 'radar voice' was streamed through VB-Cable to ten independently analyzing and doppler separating Spectrum Lab windows. TV transmitters and their carrier frequencies are on the list above detail strips and there is a freq scale in Hz above each detail strip. Bandwidths of TV carrier detail strips vary between 100 ... 200 Hz. Time stamps are Finnish local.


- Juha
Liitteet
2018-02-23 Route of mobile multi freq doppler measuring experiment to LUT on map - OH7HJ-7.jpg
Routes of mobile doppler receiving experiments were plotted with aid of an online view of ham APRS.fi. Here is the part of measuring drive from Liperi to Lappeenranta.
2018-02-23 Route of mobile multi freq doppler measuring experiment to LUT on map - OH7HJ-7.jpg (283.72 KiB) Katsottu 1138 kertaa
2018-02-23-03 long strip - Multi freq R1 TV carriers receiving experiment on moving mobile on road to LUT - RTL SDRV3 SL D1H - Joutseno BC tower bypass 1122 (c) OH7HJ - LPR VR 1140.jpg
A combined Spectrum Lab display of multi freq detail strips of TV carriers received in a moving car. Some of the carrier freq drift visible on St Petersburg and Segezha TV strips is from RTL receiver drift but much of it is caused by moving car velocity doppler shift. Joutseno TV and FM broadcast mast strong RF field appeared to deafen the RTL receiver stick at around 11.20 to 11.30 oc on this 5 TV freq strip.
2018-02-23-03 long strip - Multi freq R1 TV carriers receiving experiment on moving mobile on road to LUT - RTL SDRV3 SL D1H - Joutseno BC tower bypass 1122 (c) OH7HJ - LPR VR 1140.jpg (683.77 KiB) Katsottu 1138 kertaa
2018-02-23-1155 SDR-V3 receiving software was providing bread band radar voice - Display on mobile laptop screen (c) OH7HJ.jpg
The SDR V3 receiving software was set to stream a 22 kHz wide voice of two wide filter USB VFO's was divided to both stereo channels of a single audio stream channel. This stereo 'radar voice' streamed through VB-Cable to ten independently analyzing and doppler separating Spectrum Lab windows.
2018-02-23-1155 SDR-V3 receiving software was providing bread band radar voice - Display on mobile laptop screen (c) OH7HJ.jpg (178.92 KiB) Katsottu 1138 kertaa
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